1 00:00:00,25 --> 00:00:05,276 [MUSIC]. 2 00:00:05,276 --> 00:00:11,237 Welcome back to Calculus One, and Welcome to Week 13 of our time together. 3 00:00:11,237 --> 00:00:13,375 Well, we're almost to the end of the course. 4 00:00:13,375 --> 00:00:16,525 Soon we will be posting the final exam, which will give you a few weeks to work 5 00:00:16,525 --> 00:00:19,240 on that. But I wanted to say a little bit about 6 00:00:19,240 --> 00:00:21,599 where we are. Last week we looked at how 7 00:00:21,599 --> 00:00:25,439 anti-differentiation gives us the fundamental theorem of calculus, which 8 00:00:25,439 --> 00:00:28,799 lets us evaluate integrals way more easily than by going back to the 9 00:00:28,799 --> 00:00:34,560 definition in terms of Riemann sums. This week we continue on that quest, 10 00:00:34,560 --> 00:00:38,466 we're going to look at u-substitution which is one really great technique for 11 00:00:38,466 --> 00:00:42,865 actually finding some complicated antiderivatives. 12 00:00:42,865 --> 00:00:45,952 Now, in light of this, I also want to say a little about how the course as a whole 13 00:00:45,952 --> 00:00:49,607 has been organized. Remember way back at the beginning of the 14 00:00:49,607 --> 00:00:53,158 course, we gave the definition of limit in terms of epsilons and deltas, but very 15 00:00:53,158 --> 00:00:56,815 quickly, we abandoned those epsilons and deltas, and we gave a bunch of techniques 16 00:00:56,815 --> 00:01:01,564 for evaluating limits. Things like the the limit of a sum is the 17 00:01:01,564 --> 00:01:06,194 sum of the limits that the limits exist. And then, once we had easier techniques 18 00:01:06,194 --> 00:01:10,511 for playing around with limits, we get some applications of limits. 19 00:01:10,511 --> 00:01:13,643 A big one, being the limit of a difference quotient, which was the 20 00:01:13,643 --> 00:01:17,860 definition of the derivative. But we didn't usually calculate the 21 00:01:17,860 --> 00:01:20,750 derivative by going back to that definition. 22 00:01:20,750 --> 00:01:24,89 Usually we used our techniques of differentiation like, the derivative is 23 00:01:24,89 --> 00:01:28,864 of a sum is the sum of derivatives to make calculating derivatives way easier. 24 00:01:28,864 --> 00:01:32,203 And then we did some applications of differentiations, right, things like 25 00:01:32,203 --> 00:01:35,701 optimization problems, related rates problems, and we then did definition of 26 00:01:35,701 --> 00:01:39,282 integration, right, in terms of Riemann sums. 27 00:01:39,282 --> 00:01:42,674 But those Riemann sums were way to complicated, so we very quickly abandoned 28 00:01:42,674 --> 00:01:46,119 Riemann sums for a, a, better technique Involving the fundamental theorem of 29 00:01:46,119 --> 00:01:49,808 calculus. In this week, with use substitution, we 30 00:01:49,808 --> 00:01:53,336 learned another technique for finding anti-derivatives, that is another 31 00:01:53,336 --> 00:01:56,800 technique for evaluating definite integrals. 32 00:01:56,800 --> 00:01:59,484 And in the last couple weeks, we're going to look at some more techniques and 33 00:01:59,484 --> 00:02:03,410 some applications of integration. There's not much time left, hang in 34 00:02:03,410 --> 00:02:10,629 there. We're all going to make it to the end 35 00:02:10,629 --> 00:02:14,673 together.